Excavating apparatus with relatively slidable supporting elements



July 24, 1956 K. c. M INTYRE 2,756,036

EXCAVATING APPARATUS WITH RELATIVELY SLIDABLE SUPPORTING ELEMENTS FiledSept. 21, 1951 5 Sheets-Sheet l 242 m l R; E

INVEN TOR.

A'zxvr c? m VA 77A! BY flaw) wfwz July 24, 1956 K. c. M INTYREEXCAVATING APPARATUS WITH RELATIVELY 'SLIDABLE SUPPORTING ELEMENTS 5Sheets-Sheet 2 Filed Sept. 21, 1951 July 24, 1956 K. c. MCINTYRE2,756,036

EXCAVATING APPARATUS WITH RELATIVELY SLIDABLE SUPPORTING ELEMENTS FiledSept. 21, 1951 5 Sheets-Sheet 3 V g a Q v. an. o b 3 x, o

/64 ea; 66 l6? 3 e30 232 I 4 :4 3o 32 36 ese 2?? July 1956 K. c. MINTYRE EXCAVATING APPARATUS WITH RELATIVELY SLIDABLE SUPPORTING ELEMENTS5 Sheets-Sheet 4 Filed Sept. 21, 1951 IN V EN TOR.

Af/V? C. M Vzvrnee' ATTOAA IYS M,WM

are /2 8 y 1956 K. c. MCINTYRE 2,756,036

EXCAVATING APPARATUS WITH REILATIVELY SLIDABLE SUPPORTING ELEMENTS FiledSept. 21, 1951 5 Sheets-Sheet 5 we TEE-.15

1 gal INVEN TOR. Ai /V7 C M 01 77/94 1 QKM by means of manually-operatedair spades.

EXCAVATHNG APPARATUS WITH RELATIVELY SLIDABLE SUPPORTING ELEMENTS Kent(3. McIntyre, Detroit, Mich.

Application September 21, 1951, Serial No. 247,644

14 Claims. (Cl. 262--7) This invention relates to excavating apparatusand has, more particularly, to do with a machine for diggingexcavations, the excavation being in the nature of a relatively largeunderground tunnel.

It is common practice today to excavate such tunnels This procedure istime consuming to say the least and consequently is quite costly becausemen qualified to do such work command very high wages. Furthermore,digging tunnels of this type by means of air spades requires a highdegree of skill, and men qualified to do this type of work are not tooplentiful.

One of the problems associated with the design of a machine forexcavating tunnels of this type resides in the fact that the cutter onthe machine must be capable of cutting a relatively large hole, and atthe same time the machine itself has to be small enough and light enoughto be easily manipulable in the tunnel being excavated. Another factorthat enters into the design of a machine of this type is the requisiteability of the machine to accommodate itself to different soilconditions and the ability to excavate along an accurate, predeterminedcourse. In addition, the machine must be capable of excavating tunnelswhich extend along a contoured path as distinguished from those whichextend along a straight line.

It is an object of the invention to produce a tunnelling machine whichcan be operated by relatively unskilled labor to dig a tunnel accuratelyand very efiiciently.

Another object of the invention is to produce a machine of the abovedescribed type which is of relatively simple construction and which iscapable of being easily manipulated in the tunnel being excavated.

A further object of the invention is to provide a tunnel excavatingmachine which can be adjusted and manipulated to dig efliciently insoils which differ widely in characteristics.

A still further object of the invention resides in the provision of atunnel excavating machine which reduces to a minimum the amount ofmanual labor associated with digging the tunnel and which lends itselfreadily for use with mechanical conveyors for handling and conveying theearth excavated to a discharging point located remately from the locusof digging.

More specifically, the invention contemplates a tunnelling machine whichcomprises a longitudinally extending main support shaft on which areslidably mounted one or more supports for the machine, a rotatablecutting head and the driving means therefor, and a hydraulic mechanismin the nature of a pair of jacks which may be arranged to selectivelyconnect the shaft with the supports or with the head so that theseassemblies may be moved axially with the shaft or with respect to theshaft. The head is in the nature of a large wheel having radial armsprovided with radially staggered blades. At their outer ends the armssupport a radially inwardly opening, circumferential trough forreceiving the earth cut loose by the blades. The trough is partitionedinto rates Patent 2,756,036 Patented July 24,

2 a plurality of circurnferentially adjoining compartments so that, aseach compartment rotates to a position near the top of the wheel, thecontent of the compartment are discharged by gravity into an axiallyextending conveyor which is in turn adapted to discharge into a dump carpositioned adjacent the rear end of the longitudinally extending mainsupport shaft.

in the drawings:

Fig. 1 is a somewhat diagrammatic view of the general arrangement of themachine of this invention in its operative position within the tunnelbeing excavated.

Fig. 2 is a side elevation of the machine, partly in section and withparts broken away to better illustrate certain details of construction.

Fig. 3 is a top view of the machine with certain porlions thereof brokenaway.

Fig. 4 is a sectional view taken substantially along the lines 4-4 inFig. 3 and showing generally the construction of the extensible torquearms on the machine.

Fig. 5 is a sectional view taken substantially along the lines 5-5 inFig. 3.

Fig. 6 is a sectional view taken substantially along the lines 6-6 inFig. 3.

Fig. 7 is a fragmentary sectional view taken along the lines 7-7 in Fig.2.

Fig. 8 is a fragmentary side elevation, partly in section, of the frontend of the machine.

Fig. 9 is a fragmentary side elevation of the machine generally showingthe power unit thereon.

Fig. 10 is a sectional view of the cutting head of the gachine takensubstantially along the lines 1010 in Fig. 11 is a detail view of thedrive arrangement for the cutting head.

Fig. 12 is a fragmentary sectional view of the cutting head takensubstantially along the lines 12-12 in Fig. 10.

Fig. 13 is a View similar to Fig. 12 but taken substantially along thelines l3-13 in Fig. 10.

Fig. 14 is a fragmentary perspective view of the hub assembly for thecutting head.

Fig. 15 is a diagrammatic view showing generally the hydraulic system onthe machine.

Referring to the drawings and particularly to Figs. 2

and 3, the general arrangement of the machine includes a longitudinallyextending main support shaft 10 on which is supported the cutting head12, the power unit 14, the control jacks 16, the torque arm assembly 18,and the conveyor mechanism 20. Shaft 10 is of square cross section andslidably supports a sleeve 22 (see Figs. 2, 3 and 6). A pair of supportplates 24 reinforced by gusset plates 26 are welded or otherwise rigidlymounted on sleeve 22. Power units 14 is slidably supported on shaft 10by brackets 27 fixed on the support plates 24. Plates 24 also supportconveyor 20 as by means of brackets 25; (See Fig. 7). Referring now toFig. 9, the power unit 14 includes an electrically driven motor 30, atransmission 32 connected with the motor 39, a hydraulic pump 34 drivenby motor 30 through transmission 32, and a clutch mechanism 36controlled by a clutch lever 38 for rotating head 12. The constructionand operation of the various elements of the power unit 14 are generallywell known and need not be described. it is suiiicient to state thatpump 34 is driven continuously by motor 30 and rotation of the head 12of the machine is controlled by actuation of the clutch lever 38.

The head 12 of the machine (see Fig. 6) includes a cylindrical sleeve 40welded to the front support plate 24 to the inner face of which arewelded arcuate filler segments 42 having fiat faces which slidablyengage the corresponding fiat faces of shaft 10. Sleeve 40 supports theinner races 44 of a pair of thrust bearings 46 the outer {It races 48 ofwhich support a hub member 50. Hub 50 is retained in an axially fixedposition on sleeve 40 by means of spacer bushings 52 and 54. The frontend of sleeve 40 is threaded as at 56 to receive. locking rings 58 whichabut against the front face of spacing ring 54 and thereby maintain thehub assembly in an axially fixed position on sleeve 40. To the front endof hub 50 there is secured, as by bolts 60, a cover plate 62 providedwith a seal 64 which. prevents dirt andthe like from reaching bearing 46at the front end of hub 50. A large driving gear 66 is secured, as bybolts 68, to the rear face of hub 50 and is provided with a seal 70. Itwill be observed that the members 48, 50, 62 and 66 rotate as a unit onsleeve 40. Gear 66 is connected as by the chain drive 72 with the drivengear 74 of the clutch mechanism 36. A shroud 75 surrounds chain drive72.

Hub 50 in turn supports a diametrically split rim 76 (Figs.'10 and14)and two halves of which each comprises a pair of spaced apart sideplates 78 between which are welded split cylindrical socket members 80.In order to prevent relative rotation between hub 50 and rim- 76,. thereare welded to the outer surface of hub 50 four axially extending pins82, and each of the side plates 78 are provided with recesses 84 forinterengaging pins 82. It will be observed that recesses 84 are providedwith corresponding flat, substantially parallel faces 86 which enablepositioning of the two portions of the split rim 76 around hub 50 byseating these rim members circumferentially on the outer face of hub 50as distinguished from slipping these rim members axially over the frontend of hub 50. This facilitates assembly and disassembly of thesemembers, especially when the machine is disposed within the tunnel beingexcavated. The split sockets80 are arranged to receive radiallyextending cylindrical arms 88. Arms'88 are firmly retained in sockets 80by means of bolts 90. It will be observed that bolts 90 also serve toclamp the two half sections of rim 76 tightly around hub 50. Arelatively heavy ring 92, secured around hub 50 adjacent the rear endthereof, forms a stop against which the rear side plate 78 of the rim 76abuts. Each of the arms 88 has afiixed thereto cutting blades 94. Theseblades are staggered radially relative to one another and are inclinedto the .plane of arms 88 so that, when the head 12 is rotated andadvanced into the end wall of the tunnel being excavated, the blades diginto the earth and cut away slices therefrom.

At their outer ends, arms 88 support a circumferential trough 96 havinga bottom or outer wall 98 and spaced apart sidewalls 100. The circulartrough 96 is preferably divided into at least two half sections eachprovided with complementary socket parts 102 arranged to enclose theends of two opposite arms 88. In the embodiment illustrated, it will benoted that the other two opposite arms 88 are welded to their respectivetrough sections 96. It will be appreciated, of course, that the troughmay be formed as quadrant sections rather than half sections, in

which case the end of each arm would be received in' sockets similar tothe socket illustrated at 102. Bolts 104 are employed for interengagingthe socket parts 102 with the ends of the corresponding arms 88 and alsofor securing the two half sections of trough 96 together. In order toinsure a out throughout the radial extent of head 12 each half sectionof trough 96 is provided with a blade portion 106 which projectsoutwardly beyond outer wall 98. anda second blade portion 108 adjacentblade 106 which extends axially outwardly beyond the front side wall100a of trough 96. Blades 106 and 108 in effect cooperate to form scoopsaround trough 96, the trough being cut away as at 110 to permit the dirtcut into by blades 106 and 108 to pass into the trough. Thecircumferential extent of the trough is divided into a plurality ofcompartments by axially extending partitions 112. As is seen moreclearly in Fig. 12, it will be observed that trough 96 is supported onarms 88 such that the arms are located adjacent the front wall 100a andare spaced away from the rear side wall of the trough. An additionalblade 114 is mounted on one of the rim members 76, as by a bracket 115,and extends radially inwardly to a point adjacent sleeve 40 so that amaximum radial extent of cutting blades is obtained.

The torque arm assembly 18 (see Figs. 3 and 4) ineludes four cylindricalrollers 116 which are arranged to rollably engage the four faces of thesquare shaft 10. Rollers 116 are supported for rotation by four anglebrackets 118. Brackets 118 extend longitudinally of shaft 10 and areinterconnected so as to assume a fixed relation to one another by beingwelded at each. end to circular support plates 120. The support plates120 are centrally apertured to accommodate shaft 10. Front support plate120 has Welded thereto a sleeve 122 and rear support plate 120 haswelded thereto a cylindrical extension 124 which carries at its rear enda sleeve 126. Sleeves 122 and 126 are of square cross section andslidably engage shaft 10. The torque arm assembly is thereby supportedon shaft 10 by the rollers 116 and the sleeves 122 and 126.

The torque arms themselves are two in number one on each side of theshaft 10, and each comprises a pair of telescopically arranged cylinders128 and 130. The

outer cylinder 130 of each torque arm has four gusset plates 132 weldedthereto, two on the upper side of the cylinder and two on the lower sideof the cylinder. These gusset plates extend beyond the inner end ofcylinder 130 and are shaped such that each cylinder 130 can be slippedendwise over and into engagement with the angles 118. The straight endfaces 134 and 135 of gusset plates 132 engage with the perpendicularlyrelated faces of angles 118. A bracket 138 extends between and is weldedat each end to the gusset plates 132 on the upper portion of cylinder130. The lower gusset plates 132 are likewise provided with a similarbracket 138. The two torque arms are clamped firmly together in positionon angles 118 by means of bolts 140 one of which extends across thebrackets 138 on the top-side of the torque arms and the other of whichextends across the brackets 138 on the bottom-side of the torque arms.Each torque arm is provided with a stabilizing bar 142 pivotallyconnected at one end to cylinder 130 as at 144 and pivotally connectedat the other end to sleeve 126 as at 146. Thus, the torque arms can bedismantled from the machine by simply removing bolts 140 and stabilizingbars 142 and thereafter pullingeach torque arm endwise outwardly fromengagement with the angles 118.

A hydraulic cylinder 148 and a piston rod assembly 150 operativelyassociated with cylinder 148 are mounted in each set of telescopingcylinders 128 and 130. Cylinders 148 are pivotally supported within theouter telescoping cylinders 130 as at 152, and the end of piston rodassembly 150 is connected with the inner telescoping cylinder 128 as at154. At the outer end of each cylinder 128 there is fixed a cover plate156 to which is attached as by bolts 158 a ground-engaging foot 160preferably in the form of a pair of perpendicularly arranged plateswhich are mounted on a base plate 162. Thus, when fluid is admitted toone side of the pistons within cylinders 148, the'iuner telescopingcylinders 128 are extended outwardly to firmly engage the feet 160 withthe sidewalls of the tunnel being dug; and when fluid is admitted to theother side of the pistons within cylinders 148, the inner cylinders 128are retracted.

The longitudinal adjustment of head 12 and torque arm assembly 18relative to shaft 10 is obtained by proper actuation of the hydrauliccontrol jack assembly 16. This assembly includes a pair of hydrauliccylinders 164 each having an associated piston rod assembly 166. Therear ends of cylinders 164 are connected as at 168 with ears 170 fixedon a sleeve 172 slidably mounted on shaft 10. The outer ends of pistonrod assemblies 166are connected as at 174 with ears 176 fixed on asleeve 178 which is likewise slidably mounted on shaft 10. At its rearend sleeve 172 is provided with projecting ears'180 which are arrangedto connect with ears 182 on sleeve 122 as by pins 184. Sleeve 178 islikewise provided with lateral ears 186 arranged to be selectivelyconnected and disconnected with the sleeve 22 on head 12 by pins 188which pass through ears 186 and cooperating ears 190 on sleeve 22. Shaftis provided with a plurality of longitudinally spaced holes 192, and inorder to fixedly connect the torque arm assembly 18 with shaft 10,sleeves 122 and 126 are each provided with openings 194 adapted toregister with openings 192 in shaft 10 so that pins 196 may be insertedtherethrough. Likewise, in order to fixedly connect head 12 with shaft10, sleeve 22 is pro-,

vided with openings 198 adapted to register with openings 192 in shaft10 so that another pin 196 may be inserted through the registeringopenings. At the same time sleeve 178 is provided with openings 200 andsleeve 172 is provided with openings 202 all of which openings areadapted to register with the spaced openings 192 in shaft 10.

The arrangement just described permits the head 12 and torque armassembly 18 to be moved longitudinally with shaft 10 or longitudinallyon shaft 10. For instance, if sleeve 172 is connected with shaft 10 asby pins through openings 202 and 192 and sleeve 178 is connected withthe head as by pins 188, then when the piston rod assemblies 166 areextended the whole head 12 and power unit 14 will be movedlongitudinally forwardly on shaft 10. On the other hand, if the jackassembly 16 is pinned to shaft 10 as through the openings 200 at sleeve178 and connected with the torque arm assembly by pins 184, then it isobvious that as the piston assemblies 166 are extended the torque armassembly 18 will be moved longitudinally rearwardly on shaft 10. Thus,the head 12 and torque arm assembly 18 can be moved along shaft 10 ortogether with shaft 10. The importance of this operation will bedescribed more fully hereinafter.

At its extreme front end shaft 10 is provided with a V-shaped opening204 which terminates in a cylindrical socket 206 extending transverselythrough shaft 10 (Fig. 8). A guide plate 208 is mounted at the front endof shaft 10 within the V-shaped opening 204. Along its rear edge guideplate 208 has welded thereto a circular bar 210 which is received bysocket 206, bar 210 being engaged with socket 206 by slipping it intothe socket endwise. Guide plate 208 is thus pivotally supported at thefront end of shaft 10 and may be arranged to assume a desired angle ofinclination with respect to the horizontal axis of shaft 10 by means ofadjusting bolts 212.

The front end of the machine is adapted to be supported by a hydraulicjack assembly 214 which includes a piston rod 216 pivotally supported onsleeve 178 and a hydraulic cylinder 218 in which the piston (not shown)at the end of rod 216 is movable. Thus, by admitting hydraulic fluid tocylinder 118 to either one side of the piston or the other, the machinemay be elevated or lowered.

Conveyor 20 is of conventional construction and is driven by an electricmotor 220 mounted at the rear end of the conveyor (see Fig. 1). Thefront end of conveyor 20 terminates just short of the path of travel ofthe radial arms 88 on head 12. Thus, as the trough 96 is rotated in thedirection indicated by the arrow in Fig. 10, the earth cut away by theblades on the head falls into the compartments of the trough and isdischarged onto the front end of conveyor 20 as the compartments rotateupwardly to a generally inverted position (see Fig. 10).

Referring now to Fig. 15, there is diagrammatically illustrated thehydraulic system for operating the various hydraulic cylinders of themachine. Pump 34 is connected as by a conduit 222 with the inlet side ofan assembly of four valve blocks 226. The valve blocks 226 are mountedas a unit on cylinders 164 by brackets 225. These valve blocks are ofconventional construction and need not be described in great detail. Theconduit 228 connects the outlet side of valve blocks 226 with a liquidreservoir 230, and the reservoir is in turn connected with the inletside of pump 34 by a conduit 232. Each of the valve blocks 226 isprovided with valve spools as is conventional, these valve spools beingactuated by handles 234 to control the flow of fluid through the valveblock. Each of the valve blocks is provided with two conduits 236 and238 extending therefrom. When a handle 234 is actuated in one direction,the fluid is caused to travel outwardly of that particular valve blockthrough conduit 236; and when the handle 234 is actuated in the oppositedirection, the fluid is caused to travel out of that particular valveblock through the other conduit 238. As was mentioned previously, thevalve blocks are four in number, valve block 226a being connected by theconduits 236 and 238 with the hydraulic foot support 214, the valveblock 226b being connected with the control jacks 16, and the valveblocks 226a and 226d being connected one with each of the cylinders 148of the torque arms. As was mentioned previously, pump 34 is driven bymotor 30, and the motor 30 receives its power by means of an electriccable 240 which extends from a motor generator unit 242 (see Fig. 1).Motor generator 242 also furnishes electrical energy for the conveyormotor 220. Cable 240 connects with motors 30 and 220 through suitablecontrol switch boxes 244 and 246, respectively.

1 When it is desired to dig a tunnel, for instance, a sewer tunnel suchas is illustrated at 250 in Fig. 1, there is first excavated a verticalshaft 252 down to the depth desired for the horizontal tunnel 250. Asuificient portion of tunnel 250 is excavated such as by means of airspades to enable positioning of the machine of this invention within theexcavation. The machine is then lowered and set up for operation withinthe tunnel. In this connection it will be noted that the head 12 may beconveniently assembled on the" machine after the machine is lowered intothe tunnel. As explained previously, head 12 comprises the two halfsections of trough 96 as well as the two sets of radial arms 88associated with the split rim 76. After the trough section 96 isassembled with the radial arms 88 and the radial arms and split rims 76in turn assembled with the hub 50 of the machine, the machine is readyfor positioning within the tunnel to start the excavating operation. Theshaft 10 with the torque arm assembly 18 mounted thereon is elevated toa position generally in line with the axis of the tunnel being dug bythe hydraulic jack 214. After the shaft 10 is generally aligned with theaxis of the tunnel being dug, the operating handles 234 controlling theoperation of the cylinders 148 of the torque arms are actuated to extendthe torque arms outwardly so that the foot members dig into and firmlyengage the side Walls of the tunnel being dug. After the torque arms arethus engaged with the side Walls of the tunnel, the shaft 10 can be.aligned exactly with the axis of the tunnel by shifting the shaftvertically by means of the hydraulic jack 214 and laterally byselectively actuating the operating handles 234 which control the twocylinders 148 If the ground being excavated is relatively firm, such assolid clay, I have found that the tunnel can be efficiently dug byadvancing the head 12 and shaft 10 as a unit. If the excavating is to beperformed in this manner, sleeve 172 is connected with the torque armassembly as by the pins 184 and sleeve 178 is connected to the shaft 10by inserting one of the pins 196 through a set of registering openings192 and 200 in the shaft 10 and sleeve 178, respectively. It is assumed,of course, that at this time sleeve 178 is spaced rearwardly from sleeve22 so that, when jacks 16 are operated, sleeve 178 is shifted forwardlysuch as to drive guide plate 208 and the front end portion of shaft 10into the forward end wall 254 of the tunnel 250, guide plate 208 havingpreviously been set at the desired inclination by adjusting screws 212.After guide plate 208 has been driven into the front wall of the tunnela suflicient distance to provide adequate support for the front end ofthe machine, the head 12 is shifted forwardly on shaft 10 to engage theforward wall 254 of the tunnel. It will be noted that head 12 and powerunit 14 are in effect both supported by sleeve 22; and therefore thewhole assembly of the power unit and the head can be shifted forwardlyon shaft 10 by actuating the jacks 16 such that sleeve 17S abuts againstsleeve 22 and pushes the whole assembly forwardly, sleeve 178 beingdisconnected from shaft 10 at this time. Thereafter piston rods 166 areretracted into cylinders 164 and sleeve 178 is pinned to shaft 10 in theretracted position, and at the same time sleeve 22 is pinned to theshaft 10 as by one of the pins 196 passing through a set of registeringopenings 198 and 192 in sleeve 22 and shaft 10, respectively.

It will be observed that, with the machine thus an ranged, the shaft 10together with the power unit 14 and the head 12 moves forwardly as aunit through the fixedly supported torque arm assembly 18 when thepiston rod assemblies 166 are extended. Thus, when clutch lever 33 isactuated to cause rotation of head 12, and the operating levers 234,controlling cylinders 164, are actuated gradually and intermittently tocause the piston rod assemblies 166 to move outwardly of cylinders 164,the shaft 10 and the rotating head 12 are moved axially forwardly sothat the blades 94 and 114 and scoops 108, 106 dig into the earth at thefront end of the tunnel. The earth thus cut away by these blades fallsinto the compartments formed by the partitions 112 around the lowerportion of trough 96. As these compartments rotate upwardly, the dirtaccumulating therein falls onto the front end of conveyor 20. Theconveyor belt moves this dirt rearwardly to the rear end of the conveyorwhere it discharges into a dump car 256 which is conveniently mounted ona truck chassis 253 arranged for rolling movement on tracks 260. Afterdump car 256 is filled, it is towed along tracks 260 to the verticalshaft 252 where it is raised to the ground surface by a hoistingmechanism such as illustrated at 264.

It will be observed that the space beneath shaft 10 to the rear oftorque arm assembly 18 is unobstructed. This is quite important, sinceit permits the use of two cars 256 hitched one in front of the other.While the rearmost car is being filled, the forward, empty car isdisposed beneath the rear end of the machine. This arrangement makes forefficient operation, since it is not necessary to wait at shaft 252until the dump body of each car 256 is elevated, discharged and loweredagain onto trucks 258.

After the piston rod assemblies 166 have been extended the limit ,oftheir travel, the pin 196 interconnecting sleeve 178 with shaft 10 isremoved and the pistons retracted to permit the sleeve 178 to be pinnedto the shaft 10 at a new rearward location. The shaft, together with thehead 12 and power unit 14, can thus be further advanced a distancecorresponding to thetravel of piston rod assemblies 166. After the shaftis thus advanced through the torque arm assembly 18 a substantialdistance, it then becomes necessary to move the torque arm assemblyforwardly on shaft 10 to a new position. With the piston rod assemblies166 in the extended position, sleeve 178 is pinned to the shaft andcylinder 128 is retracted to disengage the foot members 160 from theside walls of the tunnel. Thereafter jacks 16 are actuated to retractpiston rod assemblies 166 and since torque arm assembly 18 is slidableon shaft 10 with sleeve 172, the whole torque arm assembly is shiftedforwardly on shaft 10. At this time the machine is effectively su portedin an elevated position by the hydraulic foot 214 and by reason of thefact that the front end of shaft 10 is firmly embedded in the front endwall of the tunnel. The cylinders 128 are then extended to engage theside walls of the tunnel at a new forwardly spaced location, and theexcavation operation is then continued until a new setting of thetorque'arms is required.

When the machine is. operated in this manner, it will 8 be observed thata fixed length of shaft 10, together with the guide plate 208, advancesinto the ground ahead of head 12. The inclination of plate 208 is adjusted such that the weight on the front end of shaft 10 is offset bythe tendency of plate 201' to elevate the front end of the machine. Theextent to which plate 208 is inclinedto the horizontal is, of course,determined by the firmness of the ground being excavated.

Where the ground being excavated is relatively soft, it may be necessaryto operate the machine in a manner differcntly than described above. Inexcavations where the earth is not firmly packed, the ground may notprovide sufficient support for the front end of the machine where only ashort portion of shaft 10 is advanced ahead of head 12. Under suchcircumstances, the shaft 10 is driven forwardly into the front wall ofthe tunnel being dug a substantial distance independently of head 12 andpower unit 14, and thereafter the head 12 and power unit 14 are advancedon the shaft. The shaft may be advanced through sleeve 22 by pinningsleeve 173 with a registering opening 192 in shaft 10, piston rodassemblies 166 being retracted, and operating jacks 16 to extend pistonrod assemblies 166. After the shaft is advanced into the earth, say adistance of about eight feet, or even less depending upon the firmnessof the soil, the ears 186 are coupled with the lugs 190 as by the pins188 and the jack 16 actuated such as to shift cylinders 164 and sleeve172 forwardly on shaft 10. Sleeve 172 is then coupled with shaft 10 asby one of the pins 196 passing through registering openings 202 and 192in sleeve 172 and shaft 10, respectively. Then, by operating jacks 16,it will be observed that the head 12 and power unit 14 will be fedaxially along the shaft and advanced gradually toward the leading end ofshaft 10. This process can be continued by intermittently advancingjacks 16 .on shaft 10 until the head 12 advances to a position adjacentthe forward end of shaft 10 which necessitates the further advance ofthe shaft. After the available length of the shaft is consumed, that is,when the rear end portion of the shaft approaches sleeve 126, hydraulicfoot 214 is actuated to assist in supporting the front end of themachine, cylinders 128 are retracted, and the torque arm assembly 18 isadvanced on the shaft as previously described.

Thus, it will be seen that I have provided a sewer tunnelling machinewhich is of relatively simple design but which, at the same time,renders the operation of excavating sewer tunnels a very efiicient one.The machine requires only a single operator and perhaps one or twohelpers at the discharge end of the conveyor for insuring the properfilling of the cars 256. In addition, it will be observed that theprovision of the torque arm assembly 18 and the sliding arrangement ofthis assembly as well as the jack 16 and of the head 12 and power unit14 on the shaft and the simple means provided for selectively connectingthese members together enables operation of the machine in various typesof soil conditions. It will be further noted that the slidingarrangement of these various assemblies on shaft 10 renders the unit asa whole more or less self-propelling. The head can be advancedindependently of the shaft or with the shaft through the torque arms.The torque arms in turn can be advanced independently of the shaft orwith the shaft through the head. These torque arms, which may bearranged vertically instead of horizontally as shown, in addition,provide the necessary support and resist the thrust imparted to theshaft by the head. Furthermore, when it is desired to tunnel around acurve, it will bereadily appreciated that the torque arms can beadjusted such that the shaft is inclined in a horizontal plane to theaxis of the tunnel being dug so as to negotiate a turn. Likewise, thetunnel can be inclined along a downward or upward path at any point byadjustment of the foot support 214 so that the shaft assumes a tiltedposition to the horizontal. It will be observed that support 214 isslidable with sleeve 178 along shaft 10 and therefore either the frontor rear end of the machine may be elevated or lowered by means of thissupport 214.

I claim:

1. A machine for excavating tunnels comprising a longitudinallyextending shaft, a support arm mounted on said shaft and extendingtransversely thereof, a sleeve non-rotatably mounted on the shaftforwardly of said support arm and slidable axially on the shaft, a headrotatably supported on said sleeve said head being provided withgenerally radially extending blades, means supported on said sleeve forrotating said head such that the blades thereon cut into the soil beingexcavated, means for optionally interconnecting said shaft and supportarm to prevent relative movement therebetween, and means on said shaftfor advancing said sleeve and its supported head longitudinally of saidshaft.

2. A machine for excavating tunnels comprising a longitudinallyextending shaft, a support arm mounted on said shaft and' extendingtransversely thereof, a sleeve non-rotatably mounted on the shaftforwardly of said support arm and slidable axially on the shaft, a headrotatably supported on said sleeve said head being provided withgenerally radially extending blades, means supported on said sleeve forrotating said head such that the blades thereon cut into the soil beingexcavated, means for optionally interconnecting said shaft and supportarm to prevent relative movement therebetween, and means on said shaftfor producing relative axial movement of said shaft and said sleeve andits supported head.

3. A machine for excavating tunnels comprising a longitudinallyextending shaft adapted to be positioned longitudinally within thetunnel being excavated, a sleeve non-rotatably mounted on said shaft andslidable axially on the shaft, a head rotatably supported on said sleeveand having blades thereon arranged to make a circular cut in the endwall of the tunnel being excavated, said head being movablelongitudinally on said shaft with said sleeve and means for supportingsaid shaft in the tunnel being excavated comprising an arm mounted onsaid shaft and extending transversely thereof, said arm being extendablesuch that the opposite ends thereof may be engaged with the side wallsof the tunnel being excavated to firmly support the shaft While saidhead is rotating and means for advancing said sleeve with its supportedhead longitudinally along said shaft.

4. The combination set forth in claim 3 wherein the opposite ends ofsaid transversely extending support arm are independently extensiblewhereby said shaft may be positioned such that the longitudinal axis ofthe shaft is inclined to the longitudinal axis of the tunnel being dug.

5. The combination set forth in claim 4 wherein said arm is slidablymounted on said shaft.

6. A machine for excavating tunnels comprising a shaft member adapted tobe positioned such as to extend longitudinally within the tunnel beingexcavated, a head member rotatably and slidably supported on said shaftmember, means for optionally connecting said head and shaft members toprevent relative axial movement therebetween, said head member beingprovided with blade means thereon arranged such that, when the headmember is rotated and advanced into the end wall of the tunnel beingexcavated, said blade means cut into the earth forming said end Wall, asupport arm member slidably mounted on said shaft member and positionedrearwardly of said head member, 'means for optionally interconnectingsaid arm and shaft members to prevent relative axial movementtherebetween, said support arm member extending transversely of saidshaft member and being extensible such that the ends thereof may bedriven into the side walls of the tunnel being excavated whereby tosupport the shaft rearwardly of said head, and power means comprising apair of extensible elements slidably mounted on said shaft memberindependently of said head and arm members and selectively connectableone of said elements with the shaft member and the other element withthe head member to move said head member axially of the shaft member andalternatively, said other element with the shaft member and said oneelement with said arm member to move said head and shaft members axiallyas a unit relative to said arm member.

7. The combination called for in claim 6 wherein said power meanscomprises piston and cylinder elements and including a pair of sleevesslidably supported on said shaft, the free end of said piston beingconnected with one of said sleeves and said cylinder being connectedwith the other sleeve and means for optionally connecting one of saidsleeves selectively with said shaft member or said head member and theother sleeve with said shaft member or said arm member.

8. A machine for excavating tunnels comprising a longitudinallyextending shaft adapted to be positioned longitudinally within thetunnel being excavated, a support member non-rotatably mounted on saidshaft for movement axially of the shaft, a head member rotatably mountedon said support member and having blades thereon arranged such that,when the head member is rotated and advanced with said support into theend wall of the tunnel being excavated, said blades cut into the earthforming said end wall, a motor on said support, a hydraulic pump on saidsupport driven by said motor, means for operatively connecting anddisconnecting said head with said motor to control therotation of saidhead, a support arm slidably mounted on said shaft rearwardly of saidsupport member, said support arm extending transversely of said shaftand having hydraulically extensible end portions which are adapted whenextended to engage the side walls of the tunnel being excavated onopposite sides of said shaft, a hydraulic cylinder slidably supported onsaid shaft independently of said support arm and support member, apiston rod connected with a piston within said cylinder, said piston rodbeing slidably supported at its outer end on said shaft independently ofsaid support arm and support member,

1 said cylinder and piston rod being disposed between said supportmember and said support arm, conduit means connecting said pump withsaid cylinder and said hydraulically extensible end portions of saidarm, and cooperating means on said shaft, support arm, cylinder, pistonrod and support member for selectively connecting them one with another.

9. The combination set forth in claim 8 wherein said cooperating meanscomprises a plurality of longitudinally spaced openings on said shaft,said support arm, cylinder, piston rod and support member being eachconnected with slidable shaft mounted sleeves having openings thereinadapted to register with the openings in said shaft, and including pinsinsertable in said registering openings to interconnect said memberstogether.

10. A machine for excavating tunnels comprising a longitudinallyextending shaft adapted to be positioned longitudinally within thetunnel being excavated, a rotatable head member slidably supportedadjacent one end of the shaft and having blades thereon arranged to makea circular cut in the end wall of the tunnel being excavated, a supportarm slidably mounted on the shaft adjacent the opposite end thereof,said support arm extending transversely of the shaft and beingextendable such that the opposite ends thereof may be engaged with theside walls of the tunnel being excavated to firmly support the shaftwhile the head is rotating and a second support arm slidably mounted onthe shaft between said head member and said first mentioned support arm,said second support arm being extendable and positioned generallytransversely of the first support arm to engage the bottom wall of thetunnel being excavated and means for extending said second support armwhereby when the first mentioned support arm is extended to engage withthe side walls of t the tunnel, said second support a may be adjusted inlength to control the angle of inclination of said shaft with respect tothe axis of the tunnel being excavated and means for selectivelypreventing either the support arms or the head member from sliding onthe. shaft. n

11. The combination called for in claim-10 ,wherein the opposite ends.of said first mentioned support arms are independently extendablewhereby said shaft may be supported in said tunnel by means of saidsupport arms with the axis of the shaft inclined in a horizontal planeto the longitudinal axis of the tunnel.

12. The combination called. for in claim 111 wherein said shaft isnon-circular in cross section and including a pair of sleevessurrounding the shaft and slidable axially thereon, said support armsbeing mounted one on each of said sleeves.

13. A machine for excavating tunnelscomprising a shaft member adapted tobe positioned such as to extend longitudinally within the tunnel beingexcavated, a head member rotatably supported on said shaft member, saidhead member being provided with blade means thereon arranged such that,when the head member is rotated and advanced into the end wall of thetunnel being excavated, said blade means cut into the earth forming saidend wall, a support arm member mounted onsaid shaft member andpositioned rearwardly of said head member, said support arm memberextending transversely of said shaft member and being extensible suchthat the ends thereof may be driven into the side walls of the tunnelbeing eX- cavated, said head and support arm members being mounted onsaid shaft for movement longitudinally thereof, and means on said shaftmember for moving any one of said members longitudinally of the tunnelbeing excavated relative to the other two members, said last mentionedmeans comprising a cylinder and piston assembly, a sleeve slidablysupported on said shaft and connected with one end of said cylinder andpiston assembly, and a second sleeve slidable on said shaft andconnected with the opposite end portion of said cylinder and pistonassembly, one of said sleeves being arranged to, be selectivelyconnected with either said shaft or said support arm and the othersleeve being arranged to be selectively connected with either said heador said shaft.

14. The combination set forth in claim 13 wherein said one sleeve isalso arranged to selectively interconnect said shaft with said supportarm and the other sleeve is also arranged to selectively interconnectsaid head and said shaft.

References Cited in the file of this patent UNITED STATES PATENTS1,023,654 Karns Apr. 16, 1912 1,201,097 Proctor Oct. 10, 1916 1,488,066Schmidt Mar. 25, 1924 1,500,411 Miller July 8, 1924 1,720,195 App July9, 1929 2,149,345 Hunsaker Mar. 7, 1939 2,182,477 Hollingsworth Dec. 5,1939 2,385,251 Ayers -1 Sept. 18, 1945 2,546,899 McCarthy. -.Mar. ,27,1951 2,562,841 Compton 'Ju1y 31, 1951

